Field of the Invention
The present invention relates to a technique for adjusting a color balance between a plurality of cameras.
Description of the Related Art
In recent years a so-called MR (Mixed Reality) technique is known as a technique for causing the real world and a virtual world to be seamlessly blended in real-time. One known MR technique is a technique in which a video see-through HMD (Head-Mounted Display) is used, an object that approximately matches an object observed from a pupil position of a HMD apparatus user is sensed by a video camera or the like, and the HMD apparatus user can observe an image in which CG (Computer Graphics) is superimposed on the sensed image.
Japanese Patent Laid-Open No. 2004-205711 discloses, as an MR system that uses a video see-through type HMD, a technique that uses an HMD provided with a first camera that senses a field-of-view region of a HMD user, and a second camera that senses an image in order to detect a position and orientation of the HMD.
Japanese Patent No. 4522307 discloses, as an MR system that uses a video see-through type HMD, a technique for causing brightness or color in left and right sensed images from sensed luminance information to match among a plurality of cameras for a right eye and for a left eye.
However, the techniques disclosed in the above-described patent literature have a problem as below.
Japanese Patent No. 4522307 discloses using a common luminance value, obtained in accordance with processing for averaging luminance from a plurality of differing pieces of luminance information sensed by a plurality of cameras, to perform WB (white balancing) correction control in a unified manner. However, in the technique disclosed in Japanese Patent No. 4522307, if a characteristic, a setting, or the like among the plurality of cameras exceeds an allowable range, it is not possible to perform unified WB correction control in which color matches among the plurality of cameras.
Japanese Patent Laid-Open No. 2004-205711 is also similar; in a configuration in which cameras (image sensors) of differing types are equipped as is disclosed by Japanese Patent Laid-Open No. 2004-205711, there is a problem in that, for reasons such as the image sensors being different or luminance adjustment processing being performed in accordance with a purpose where the purpose differs, it is not possible to hold a common luminance value between a plurality of cameras, and unified WB correction control is not possible.